Arc plasma’s electron number density diagnosis by the measurement of the refractive index

In this paper, arc plasma’s electron number density diagnosis by measuring its refractive index distribution is studied, while both the indirect and direct methods are discussed. As a result of the temperature imprecision will be carried into the reconstruction of the electron number density distribution in the indirect methods, the direct methods are preferred and schemed. For the direct methods, two reconstruction models which can directly obtain the electron number density distribution are compared, meanwhile, the unity and diversity of them are proposed. Besides, the involved electron number density reconstruction imprecision is analyzed. In short, this study will provide some reference on arc plasma’s electron number density diagnosis by the optical methods which are based on the measurement of the refractive index.